Years of rule changes designed to help the offense at the expense of the defense, the evolution of coaching, and the good weather of the early season have combined to create a game of football that's almost entirely based around passing. Whether it changes or not at some point down the line remains to be seen, but, for now, you can't win in the NFL if you can't put up huge numbers through the air.

Luckily, the Giants can do that. Eli Manning's performance in the fourth quarter against Arizona made that clear as he picked apart the Cardinals defense to bring his team back for a win that seemed unlikely when they fell behind by 10 points.

When we try to figure out why the team fell down by 10 points, though, we're forced to look at the other half of the Giants offense. As good as Manning has been, that's how bad the Giants rushing game has been through four weeks of the season.

The Giants rank 24th in the league with 87.5 rushing yards per game, a number that could represent a shift in focus to the pass if it wasn't for the fact that the Giants haven't been particularly pass-happy. Ahmad Bradshaw and Brandon Jacobs have gotten chances, they just haven't done anything with them.

Figuring out why the running game is down offers many possibilities: There are two new starters on the offensive line along with a new tight end and fullback. There are defenses loading the box to force Manning to beat them. And there's Kevin Gilbride's generally erratic play calling that went away from the run in the opening loss to the Redskins.

Whatever the reasons, changing the results around this week could be tough. The Seahawks are holding teams to 3.3 yards per attempt and the Giants could be without center David Baas, who was injured last week, and Jacobs, who hasn't practiced this week because of a knee problem.

So far, the Giants have been lucky enough to get great performances from Manning, who is off to the best start of his NFL career, so that their lack of a ground game hasn't been crippling to the offense. When they start facing better defenses, they might not find the same kind of success while being so reliant on one phase of the offense.

We can't know if things will work out that way, but we do know that this Giants team has worked its way through a bunch of problems already this season. That provides some confidence that a breakthrough on the ground isn't too far away.